Elevator.



G. D. SBEBERGER.

ELEVATOB. APPLIUATION FILED om'. 21, 1903. mmwm) DBO. a. 1909.

Patented Aug. 8, 1911.

1l BHBBTSWSHBET 2.

G. D. SBEBERGBR.

ELI-NATUR. APPLIoA'rIoN FILED o'r. 21. 1003. BBNBWED DEU. 2, 190g.

Patented Aug. 8, 1911.

C. D. SEEBERGER. BLEVATOB. urmonmu FILED our. a1, moa. nnnwsn Dro. 2,1909.

Patented Aug. 8, 1911.

11 SHEETS-SHEET 4.

C. D. SEEBBRGER.

BLEVATOR. nruorllox FILED 001'. 21, 190s. Bmmwnn D20. a. 1909.

Patented Aug. 8, 1911.

11 SHEETS-SHEET C. D. SEEBBRGER. ELEVATOR APPLIUATION FILED 00T. 2

1, 1903. BENBWED DEU. Z, 1009.

u D. SBBBBRGBR.

BLEVATOR. APPLIUATION FILED 00T. 2l, 1903. BBNEWED DBO. 2, 1909.

999,885. Patented Aug. 8, 1911.

11 SHEETS-SHEBT 8.

U. D. SBEBERGBR. BLEvAToR. APPLIOATION FILED 00T. 21, 1903. RENEWBD DBO. 2, 1909.

Patented Aug. 8, 1911.

o. D. SEEBERGBR.

ELBVATOR.

APPLICATION FILED 00T. 21, 1903. EENEWBD DBU. 2, 1909. 999,885. Patented Aug. 8, 1911.

CHARLES D. SEEBERGER,

or Naw iroax, N. Y., Assionon To ons ELEvA'ron COMPANY, A coaroan'rron oF NEW JERSEY.

ELEVATOR.

Spccillcation o! Letters Patent.

Patented Aug. 8, 1911.

Application led October 21, 1903, Serial No. 117,878. Renewed December 2, 1909. Serial Nm 591,070.

To all whom 'it may concern: Be it known that I, CHARLES D. SEE- nnncnn, a citizen of the United States, residl concerned with various features of improve ment for an elevator in which a single endless series of steps running in duplex splrals about a common well or center of curvature is employed for conveying urp'oses on both the ascendn and deseen ing spiral runs or right and left threads.

The invention consists in the matters hereinafter disclosed and pointed out in the appended claims. y H

The principles of my invention maybe embodied in practice in various forms and exemplications, and the accoinpanyin drawings show preferred arrangements an organizations `in which its various features may be realized. l

In these drawings- Figure 1 is a perspective view of a design for a duplex spiral elevator embodying the features of my present invention, and showing the same extending between a lower and an upper level, and also illustrating one arran ement for the upper level that maybe emfpoyed, the drive mechanism bein omitted or greater clearness o f illustratmn; Fig. 2 is a diagrammatic view of the Hoor plan at the lower 1evel,vindicating' 'the first floor or landing, and showing in plan view the beginning of the ascending run and the end'of the descendin run; Fig. 3' is diagrammatic view of the oor plan at the upper level of Fig. 1, and shows in plan view the upper end of the ascending run and the stairs leadin down to the gallery for the descending lan ing of Fig. 1; Fig. 4 is a diagrammatic view of the arrangement of the gallery for the Adescemiling 'landing of the upper level when the arrangement a'ft the u per level illus- "trated in Fig. 1 is employe und also showing in plan view the beginning of the descending run and anintermediate portion of the ascending run; Fig. 5 is a diagrammatic view showing the arran ement 4and-organization at the upper leve when the ettingoff and getting-on landings are .'on t e same door or level, whereby the gallery arrangement of Fig. 1 is not employed 6 is a' plan view of two of the steps when they4 are on the ascendmg run, the tread of one of the a serles of steps of which the two at the right are shown running by their truck- Wheels on inclined curved tracks of the ascending run, the middle three running by their truck-wheels on curved horizontal tracks of the landings, and the two at the left running by their axle-wheels on horizontal straight tracks at a tan ent to the curved tracks, the outer linkage eing omit ted for simplicity of illustration; F1 8 'is a view showin a series of ste s in ,si e-ele`- vationof whic the two at the eft are' in the positions and relations occupied b steps on the inclined curved tracks, and the'twoat the right are on curved horizontal tracks of the landings; in this view the axles are in section, the axle-rollers being omitted for Abetter illustration of the other arts; Fig, 9 is a view similar to Fig. 8 and s owing the arrangement' of linka e employed at the outer convex` ends of t e steps, the ends of the axles beingl in section; Fig. 10. is aj detail view showing in side elvation the arrangement of linka e employed at the inner con cave ends of t e ste s, the ends of the axles being in section; 11 is a'sideyiow of one of the. links of `g. 10 detached,with the axle of the next step in section; Fi 1Q is atop planview of the inner linkage 1 lustrating the three ositions which adjacent s teps being Iomitted to show the constrc- `tion o f the carriage; Fig. 7 is a plan view of axles assume at di erent onts iliithe course or cycle of` the steps; ig. 13 is a partly cross-sectional view on the s iralruns showing the arrangement of trac s for the truckwheels o the inclines; Fig.' 14 is asimilar view sho ling the arrangement of the tracks i for the truck-wheels on the Vcurvedlevel landings; Fig. 15 is adia animatie view showin the arrangement o the drive mechanism; li 16vis a detail view of one of the` vertical rive shafts lwith its associated sprockets, illustrating the connections tothe ascending and descending runs; Fig. 1'? is a diagrammatic view showing the arrange# ment of parts and illustrating the movements of the steps in the upper carriage or loop' Fi 18 is a sectional view on the line A- o Fig. 17; Fig. 19 is a view similar to Fig. 17 and showing the movements of the steps in the lower loop or carriage; Fig.

is a sectional view on the line B--B of Fig. 19; Fi 21 is a sectional view on the line C-C o Fig` 19; Fig. 22 is a front view of one of the steps showing the riser; Fig. 23 is a diagrammatic view illustrating the method of plottin the lines of the riser; and Fig. 24 is a iagrammatic view illustrating the curves Vat the outer andr inner ends of the riser.

In the embodiment of my present inventionl I 'em-ploy a carrier or the footway consisting of a sin le series of ste ls, preferabl onnected to et er as hereina ter describe which ascen from a lower to an upper level or levels in a lspiral path or course, and devscend from the uppler to the lower level in Vso \ guard-railsor 'balustradee which ma a second spiral pa ing run being below or under the ascending runv or vice versa in the same circular area and preferably having the same center -of curvature. It is obvious that the steps may be continued and carried between as many levels or floors as is desired, and the exempliiication here given of-an organization ,running between only two level.; or lloors is merely illustrative of the general scheme of-arran ement, which of course may be developed y duplication for additional levels.

VOn the'inclines betweenv the floors orV levels they run onr curved horizontal or le'vel tracks, while at. the yterminal levelsv they run around loops in which portions of the tracks are preferably -straightand at tangente to the curved tracks, although the carnage. ap- 'preach ma be designed without' the introuction o tangente. As `I. employ but a sinle series of steps for 4'the entire cycle inclu ing the reversely directed spiral frans,

I provide a construction i. and organization in which the tread surfacesof the steps or carriages remain hrieontalfand uppermost on both the ascending and 4'descending runs. At the terminal levels the steV s are inclosed in any suitable casings whic conceal and or conveying pur protect .1 the partswhere they are not used` ses, and between the not .require any particular description.

" AReferringnow to the views shown in Figs.

f 1,' 2, 3,4,"and 5, -whichillustrate the path y the general design o'the elevator shown in Figs; 1 t4); 4. 'gf movement' `manina or-:course of the steps, I will {ir-st describe 1,11 'these the directionsI steps'are indicated by h ltions oimovemcnt of "YF indicated or course, the descendvarious levels spira structures are provided ceases by featherless arrows. Also, the steps on the inclines are indicated in full lines und those on the landings by dotted lines for convenience of illustration. lt may be assumed that the passenger boards the steps of the elevator at the lower landing of Fig. 2, where the steps emerge from below the floor .1 of the lower level 'to form the lower getting-on landing 2. At this landing the steps run in a horizontal curved path with their treads or upper surfaces in horizontalalinement, and then immediately ascend upon the inclined curved or spiral path provided by curved tracks or wayson the spiral structure 3, as hereinafter described, and the passenger is carried along the ascending curve indicated by the arrows 4, until he reaches the upper level or second story 5, where the steps again run in a horizontal curved path with their treads in horizontal alinement to form the getting-ofi' landing 6, and where a shunt 7 may be employed. to assist the passenger in .a ighting,

as shown in Fig. 3. After providing the lunding', the steps may pass beneath the floor of the upper level 5, and are preferably led in a horizontal straight run at a tangent to the ascending incline to a point where they pass down in a casing 8 to a gallery 9, to which suit-able stairs l0 lead from the upper lioor orlevel. When they reach the gallery they are preferably led below the floor in a reverse straight horizontal run at a tangent to the descending run or incline, emerging from below the ioor of the gallery 9 and then running in a curved horizontal path with their treads in alinement to form the up er getting-on landing 11, from where they' egin their descent 1n the descending spiral ath represented by the arrows 12 provided by curved tracks on the spiral structure 13. The passenger having boarded the descending run at the gallery 9 is conveyedto the lower level or story, where the steps run in a horizontal path with their treads in alinement to form a getting-oil landing 14, and where a suitable shunt 15 maybe employed to assist in alighting. The steps may pass below the floor at the landing 14, and continue in the curved path until they pass to a point approximately under the getting-on ending 2 where they go into a straight or v level run 16 tangent' to -the inclines and thencethrou h the lower loop or carriage, hereinafter dzescribed, to a straight or level runV tangent to the landing 2 where they emerge from below the floor and pass in a curved horizontal run to form this landing. It will thus appear that the steps pass around top and bottom loops or carriinzes,V

and travellin a double spiral path in making a complete cycle of the machine, the ascending and descending runs on the inclines being preferably in' the same vertical planes i ant upper getting-on and getting-off landings at Various points and traveling about a com-- mon cent-ral well of which thc center is the center of curvature ot the spirals; for cxam le, it will be apparent 'from Figs. 1, l

r4 that the initial steps of the descend4 ing run aie below and in the same vertical .plane as the final stops of the ascending run,`

and that the path of the dcscerulilxg run follows below or underneath the path of the ascending run for-its entire length, the terminal of the descending run being below the initial steps of the ascending run. The' latter is apparent from an vinspection of Figs. 1 and 2.

In the form just described the descending run is below the ascending run, but it is obvious that either run may he above the other as the ascending run may be below the descending run. Also, in the form shown the center of curvature of the two runs or paths is the same, and it is obvious that the runs may be on compound curves.

The arrangement and organization at the upper terminal level may be varied so as to do away with the gallery and to have the 6 and 11 upon the saine iioor or level. For example, in Fig. 5, I show a design where the getting-olf and getting-on landings t5 and 11 of the u per floor are upon the same level. In this form the ascending run beyond the getting-olil landing 6 is carried around a loop 17 above the iioor of the upper level and is returned to a point beneath theV tloor of the upper level from which it emerges at the getting-on landing 11 l n the present application I make vno claim to this latter construction or arrangement as the s ame forms part of the subject mattervof my companion application, filed Feb..26, 1906, Serial No. 302 760, renewed Mar. 26, 1910, Serial No. 551,'174, in which it is claimed. p

The above description applies specifically 'to the forms shown in'which the steps 4-are utilized 'between tivo levels, and it will be understood that 4where they are ccntinnedto or` levels, the spiralV other higher landin V structure will be uplicated between the added floors and the steps will 'be led around a suitable loo at the uppermost or terminal level. that landings may be provided between the levels as occasion may require, and thatv each may be constituted by a single step I or by several steps traveling horizontally according to the interval of time desired lin which the passenger may act.

5 The steps remain with their tread surfaces u perinost and horizontal upon the curved horizontal landings, 'at each of which they lie in the same horizontal plane to ".form a level latform, and upon the `curved inclines of t e ascending and fescending It will also be understood' runs where they lic in different horizontal planes in the Vform o1 steps, as clearly shown in Figs. 8 and 9. ll shall now describe their cmxstruction, interconnection and method ot' operation, referring more particularly to ll`igs. 6 to 12.

llaeh step comprises u horizontal portion or tread 18 provided. with a suitable riser 19 and end pieces 20, which are suit-ably scoured to the brackets 2l of the trucks 22. The shape of the steps will depend on the radius ot tlul curve in which they run, the horizontal tread being segmental in its gein eral outline, its sides converging toward the center of curvature of the spiral run and its inner concave end being slightly shorter than its outer convex end, as clearly shown in Figs. ti and 7. In the particular form of elevator shown, each tread is provided with a single riser of suitable contour to maintain Contact with the adjacent step and which performs its :function on both the ascending and descending runs, hereinafter described.

Each truck is provided with arms 23 and 24 constituting yokes in which the shafts of the truck-Wheels 25 and 26 rotate in bearings,the pairs of Wheels on cach step being keyed* to their respective shafts 27 and 28 to produce uniform movement ot' the wheels. The trucks of each step are further provided with bearings for a step-axle 29 to which inner and outer wheels 30 and 31 respectively are suitably keyed. The truckwheels 25 and 26 of each step are adapted to runI on inclined curved tracks 66, 67 and 68,'69, respectively, when on the inclines, and on curve'd horizontal tracks 70, 71, and 72, 73, res ectively, which are extensions of the curve tracks when at ,the landings,

`and the wheels 30 and 31 are adapted to run on strai htor talgent tracks 74 and 7 5, re spective y, beyon the landings at the ter'- -minal levels, the arrangement being such that the ste s are carried or supported by lthe truck-w eels while on .the curved tracks and by the axle-Wheels while on the tangent or ,strai ht tracks. For this purpose 'the treads o the axle-wheelsand 31,' are 'ofthe same size or diameter, while the diam eter of the tread' surface of each innerY tluck-wheelis enou h smaller than the diameter of the trea of its associated outer i Wheel so that the tread of the inner wheel will pass over enough less` actual length of Atrack than 'theassociated' outer wheel to 31 therefore are beyond or outside the .i

wheels of these shafts, while the shafts 27I of the wheels 25 are in turn longer than the .shafts 28 of the wheels 26, as will appear tracks, as clearly shown in Figs. 13 and 14.v

The tread surface of the inner wheel 25 is therefore the smallest in diameter, that of the inner wheel 26 being next larger, that of thc outer wheel 26 being next larger, and that of the outer wheel 25 being largest, as also appears from Fig. 13. Theinner track for the inner wheel 25 is raised above the outer track for the outer wheel 25 at any cross-sectional point on the inclnes a distance equa-l tothe difference between the lengths of the radii of the two wheels, and the saine relation is observed with respect to the tracks for the inner and outer wheels 26. The tracks for the inner truck-wheels and the tracksV for the outer wheels are respectively separated in .elevation a distance equalv to the difference in the lengths of the radii of their respective tread surfaces. This organization is clearly shown in Fig. 13. v

As the truck wheels 25 and 26 run on inclined tracks, the yokes are made angular in side elevation. The arms 24 of the yokes are of such length that the shafts 28 are out from under the body of the associated step, the objects being to' have the wheel base' broader than the tread of the step to insure stability and as the arms 24 of the yokes of each step project downwardly and laterally beyond and under the shaft 27 'of the next step, they provide for interlocking adjacent steps, for which purpose they are provided with recesses 32 in their upper surfaces to form seats for the shaft 27 of the next step when the steps are on the incline. Each shaft 2T is preferably provided with tilted,1

collars 33 having flanges 34 which embrace the sides of the arms when the collars seat in the recesses to prevent any lateral. displacement. The `singularity and shape of he yokes are such that when adjacent steps are on either the ascending or descending),` incline, the collars of each shaft 27 are seated in the recesses of the yoke of the next step, whereby the steps on the incline are locked together to make a. rigid unitary series. This construction' is shown in Figs. 6, 7 yand at the. left of Figs. 84 and 9. When the steps are off the inclines and upon the curved level runs, the tracks for the wheels 25 and 26 are placed ati,y different levels, those for the wheels 26 beingh below those for the Wheels 25, as shown in Fig. 14, in order 4.that the treads will aline in a horizontal plane to 4make annnbroken landing. The effect of this arrangement-.is to drop the arms 24 away :from and below the shafts 27,' whereby the collars 33 are disconnected from their seats, as shown at the right of Figs. 8 and 9. By the organization here disclosed the steps are caused to automatically interlock on the inclines `and unlock on the levels, so that they are added one by one on both the ascending and descendingr incline to form a rigid unitary structure, and are broken oil one by one at the levels. The interlocking of the steps maintains the equilibrium of the steps, prevents any inde endent or separate movement of any indivi ual step, and causes thc ent-ire series on the incline to move as a unit. This is an important consideration as ,in a spiral elevator all thrusts are toward the center. and the interlocking of the-steps resists all lateral thrusts by holding the steps in their radial relation; also, in devices of this character where the steps must change on the levels from their relative position on the inclines, it is necessary to provide t ieir permanent connections with more or less adjustment, and bycansing the steps to interlock on the inclines the permanent connections may be made adjustable to accommodate the different positions on the levels and inelineswhile la rigid connection is assured throughout the range of their use on the inelines. Moreover, when power is applied to this unitary series of steps, at any point, it is in effect positively distributed through out the interconnected series; by reason of their connections the steps are in eifect one piece. Also, 1Whenthe step-frames or yokes interlock, it is obvious that the tracks for the truck-,wheels of the axles 27 may be omitted on the inclines, so that the steps may run on the inclines as two-Wheel steps and are interlocked to make arigid unitary structure supported only by the wheels 26 it desired. lt is apparent that this greatly redures the friction of the machine. A

The steps are connected at. their outer and inner ends `by suitable linkage, the connection between the steps at one end being con stant and at the other end being variable or adjustable. In the system here shown the constant connection is on the outer linkage. Tn Figs. 6 and 9, the outer linkage is shown as consisting of a series of curved links 35, which are, pivotally connected to adjacent axles 29. Each link is pivoted at its 4opposite ends to collars and 37 on adjacentaxles by means of vertical pins assing through yokes 38 on the links an inter mediate ears 39 on the associated inner and outer collars. Each axle 29 is provided with a wrist 40 which loosely receives the collars and upon which they are suitably held. Each link connects with an inner collar at one end and an outercollar at its opposite 125 The inner endrof each axle 29 is provided .1.39

i. 4'and having a late which a link 44 i v 6 Passing thx-ou 'A ink 44 is provlded n elongated horizontal incassi:l

hooks are again disconnected by reason ot' the an le made by the links, wliereby'the link o the leading ste is freed from the hook 48 of the secon step and its axle passes to the outer end of the slot of the link 7o of the second ste 'as shown in Fig. 1l und at the right of Fig. 12, when the steps lin-iw out to bring the axles into .parallelism on the straight runs. On the reverse inn, the axle of each siicceedin 75 tionof Fig. 11 as the steps more over the and when they strike the nl tracks st the getting-on again interlock on the hooks en thcv leading step passes to 8o incline, these hooks are disnlar relation of the ollowing step is upon are aiain iilined and oc in which posi-- :line

with a'wr'is 4l sleeve 42 located ral projection or ear 43` to s pivoted by a vertical pin gh its yoked end 45. Each ear its free end -witli an slot 46 which receives 429 of an adjacent step` Each g step is in the posi which freelyy rotates in a outiiide the axle-Wheel 30 in g next tangent tracks, curved horizont landing 11 they 48 and 50. Wh the descending connected by the a links, and when the t? cterl by the the incline the links travel over the descending im he steps reach the lower level thc ien the leadt the wriston the axle as clearly shown in Figs. 10 and 11. 10 wrist-is provided w" an annular retainlili, 47, andtlie body of the link of the lies between this [in and the associated 10,y to prevent the t, the arrangement the wrist may move from slot but the link and wrist the hooks 49 and 50 inter] 85 tion they When-t hooks 4 angular relation of the links wl ing and second steps' the curved horizontal and curved inclined ding and second ste is ing-off landing run tie age by reason of the s while their steps are 95 aal-ing step .passes l rim of this landoor it. is slightly the track and these col a1' 42 as shownin Fi displacement of the lin being Asuch that end to end of the are not `disconnected- A The links are slightly o'set'or curved away from the ste s at their outer or free ends, as shown in lgs. 6 and 12, whereby when thesteps are on the curved '-'tracks the links will not interfere with each other. In practice the links are thicker near their pivot-al ends b reason-of suitable strengthening' webs wh'ic overhangthe fins 474 exce t when the latter are near the free ends o the links,v this construction causing thev ribsto appear `in dotted lines in some instances, asin- Fig. 6 and at the left in Fig. 12. At a pointap'proximately at the center of the slot', 46,' echlink is rovided on its uppersurfacewith a pair o inglho'oks'48 and49, and ne end with ,an'op' ositely'or outwardly .facing liooks being all arranged in VWflien the stepsare on the es are alined as shown by of Fig. 10, and the cent steps are connected 9 and 50 aredisconne are respectively upon tracks; when thel lea 'are both on the gett hooks 48 and 50 eng alinenient of the link on that run; whenl the le from the curved horizonta ing down, through the fl depressedby a drop in hooks 48 and 50 are dise following axle again ass of Fig. 11, in which relati 4the steps return to the ge ngaged so that the 1'00 urnes the position on it remains unt-il tting-on landing 1. Upon the curved horizontal tracks of this l landingthe links again aline to rengage on the' hooks 48 and .50 which coact during the run over the tracks of this landing; lwhen the leading step strikes the incline the angular relation of theV links causes these hooks to disconnect, and when the sncceedupon thelincline the links n'gage on the hooks 49 and bvluus that when the e distance from owing axles will U5 by the engagemen -40 hooks 50', cron 'th as shown-1in F 10 and 12.- Assirn'in 10 aremovin from left to right u cline,'w,hen t e a'xle 29 of a leading Astep 45 reachesa' horizontal or level ran it drops in relation tothe l llowingi L,fpiiis clearly' ingJatep also comes shown byrthe' two intermed a e axles in Fig. fjline to rel! 10, and the hooks. 49 Van ,50 are discon-A U as efore. It is o nected. VVhenthe succeeding or second link steps are on the incline '5 passes to the horizontal run itqagain' falls any hook 50 to the next lo into line with the first 'or leadin link. as be greater than the distance between the Shown by the two' links ati-the rig t of Fig. 'same points when the steps are on the curvedV 10, and-in this a'lined .position the hooks` horizontal runs,vby-reason of the differences gain brought into operative inV elevation causedV by thegradient of the .hookof the second link This difference is equal to the 1.304, y engagesthe short hook,-48 of 8 and 49, sov 7 k, or.4 the links 'areconnected for justs itslf n inwardly facar its pivoted 4.hook `50, these 35 [the same line.. incline the` axl the two axlesatthe left' inner linksaf Aad'iai l of the hooks 49 'with the e longest hooked length 6 and at the left of Fi that. the parts ,in Fig.

the ination inclines.

istance between the ,hooks 4 that the linkage automatically toconnect the axles in either rel i the inclines the inner linkage is about an inch and a quarter lon ithan on thehnrijzontal curved runs, wile-it is `about ten gerI when the steps run on` the tan nt tracks at the carriages. e-relatio'n ofeach hook .50 withrefer- `once to theaxle 29 of its associated. sleeve, 133

, on the links are a 55 relationand the a'ut'omaticall the first lin l the. curved horizontal landing'A rim on the shortesthoo l l stepsV travel over thelcnrvedlanding. This positionV is ,shown at the g find at the ri'ght'o Iiigfivlfl. When the in 4st ..passesunderhthe floor atthe ending it is'slightly de# y. i'rdrcnfin the track; and the inches lon ked length, in which relation the mitdleaxle ofFi gage and the relation of the hook 48 with reference to the inner end of the slot of its associated link are such that when the hooks 48 and 50 are engaged the axle is at the inner end of its associated slot so that there is a positive and fixed connection at that oint between the associated adjacent axles. Ivhen the links are `unhooked the engagement is at the outer end of the slot, as in Fig. 12, and when the hooks 50 and 49 enthem. These parts provide means to allow proper and necessary adjustmentof the connections between the steps on' the ends where the relations of the step axles vary, and also provide for the automatic enga ement and disengagement of these adjustaile connections.

The outer and inner links are preferably in the form of rack bars in order to apply power for moving the steps. The lower edges of the outer links are provided with teeth 51, and their lower portions extend somewhat beyond the yoked ends 38, as shown in Fig. 9, .and overlap in all positions so that the teeth form continuous rack bars. Each inner link 44 is provided with a def' pending web 52 which .extends romfbelow the oke 4 5 to apoint below the hooks 49, so t at 'while the steps are running on the curved portions of track on the inclines and on the curved landings the webs form aractically continuous length as they will ap,as clearly shown in Fig; 10. `The lower edges of the webs are provided with teeth 53, whose pitch is so arranged that the teeth on adjacent links are inline radiallyj or transversely on either length of 'the linkage on the hooks 48 or .49. The links 35v and 44 being pivoted to their associated collars in one plane, and the collars being in turn journaled on the axles in another plane, the

connections are ,those of a universal oint,

Vand the racks. are curved approximate y onI the arcs rof circles of which the cent/er is the centerof curvature of the curve 'tracks Power to drive th'esteps may e applied in any suitable manner, in a double spiral path around the axis'of the central well, I preferably employ suitable drive shafts grouped in the central well to distribute and apply ower to the steps at various points on the inclines. In order to synchronize the movements of the'drive shaft-s, l prefer to drive `them all from the same central shaft to `which a suitable motor is connected. The driving mechanism may be located at any level, and preferably is in the basement.4 In the form shown it consists of a suitably driven short central shaft 54, having ,a gear Wheel 55 which is' adapted to mesh with a serios of gear wheels 56 on vertical drive shafts 7`m;ranged at suitable intervals about the power shaft 54.

.pinion the engagement is formed betweenv von the links. the shafts 57 and 'ascending and descendiglg aft will gear with and as'lthe steps run intervals in the path of the steps.

,on the In Fi 15 I have shown six drive shafts ar range in the well, although any suitable number may be employed. These vertical drive shafts extend upward alongside the spiral runs in proximity to the course .of the steps and are adapte to impart motion thereto. Each drive shaft is provided with a-bevel gear pinion 5`8xwhich meshes with a correspondln bevel lgear 59 on a radial sproc :et shaft 60. The radial sprocket naled in the frame of the spiral structure or casing, and each such shaft is provided-With driving sprockets 61 and 62 arranged respectively near its inner and outer und in ti e paths of the teeth of the inner and outer links respectively, the diameter ofthe inner s rocket bein proportionately less than the ath or iameter of t e outer sprocket according to the relative speeds-of the inner and outer ends of the steps, and the width lol the sprockets bein suicientto engage the teeth such that their rotation drives' the Asteps in the proper direction. Each drive shaft 57 extends upwardly alongside the spirals; if the `steps run'fbe extend ,-u and they ^.w 1llbe extended according to the number lof-levels reached by the steps; By

he gear connections between' t e sprocket'shafts 60 are Ween two levels they will-V the doors of these levels, j

reason of .this fact each drive shaft will be A adjacent to or intersect each of thev ascending and descendingnms at one point at least between each two levels. Where each drive shaft f intersects rive shea .with heath@ runs or spirals it tersection of each follows, that each such both the ascending and descending lines of.

stairs. For this 4purpose each drive shaft is reversely geared with the radial shafts as sociated ywith and driving the reversely. directed runs, as shown in Fig. 16. -The employment of this organization serves to balance the load ,of the ascending and descend' ing lines of /ste s, and reduces and equalizes the torsione strains o n the dri-ve shafts.

I prefer to employ radial idle shafts 63 `Which aresultably journaled in the casin or frame ofthe spiralstructure ntermedb4 espiral it gears with `a sprocket shaft 60 and by reason of the iulos ate the shafts', and ar@ provided with inner and outer sprocket wheels 64 and 65 respectively, These idlers serve to, synchronize the elevator insure the radial positions of the step axles, prevent one end of the step axle from getting ahead of the other, and equalize the strains due to the lateral thrusts of the parts. These idlers are disposed at suitable As the aseendig and descending runs are curved ame center in the design here shown,`

which mesh with the links.'

it follows that all the radial shafts and 63 are on radii of the same circle, as illustrated diagrarnrnatically in Fig. 15.

The tracks upon which the steps run are supported by any suitable means, such s plate girders, carried by the stationary structure. The relatively wide gage tracks (5h, (S7, for the inner and outer truck wheels 25 respectively, and the narrow gage tracks (38 and 69 for the inner and outer truck- Wheels 26 respectively, are supported on the spiral structures and extend in inclined spirals or curves from level to level. The arrangement of these tracks on the inclines is clearly shown in Fig. 13, and the steps travel thereon in step-like forni, it being apparent, however, that but a single track is necessary on the inclines when the trucks or steps interlock as before described.-. At

vthe levels the tracks are projected in curved horizontal paths as at 76, 71, 72 and 73 to form level runs so that the threads of the steps on the gettingpn and getting-ofi land ings will have their upper surfaces in alinement to form landing surfaces of unbroken continuity, as shown in Fig. 7. Ou the curved horizontal paths Vat the landings Where the treads are in the same horizontal plane, the narrow gage tracks 72 and 73 are slow the tracks and 71 a distance sutilcient'to accommodate for the singularity of the trucks, as clearly shown in Figs. 8, 9 and 14.

When the steps run on the tracks on the inclines and landings, the wheels 3() .and 31 of the axle-roller are inoperative. At the landings and extending away from ther inclines, I provide straight horizontal tracks 74 and 75, 4which vare tangential to the curved tracks and support and carry the axle-rollers 30 and 31., respectively, upon which the steps run as they leave and ap proach the curved horizontal runs of the landings, as shown in Fig. 7. The curved tracks do not support the steps when V`the rollers 30: and 31 are upon thetangent tracks, the adjacent ends of the curved and tangent tracks beingpteferably arranged in suitable manncr,however, to provide con tlnnuous supports for the steps, and the curved horizontal tracks leading;r beneath the floors of the levels to the tangent tracks. rIhe tangent tracks Vpreferably develop into channel,.-tracks which extend around the upper and lower loops or carriages at the up- .per and lower terminal levelsl in suitable portions of the casinar or frame. When 4the 'steps pass the gettingol landing 6 at the' upper terminal level, the wheels 30 and '31 env age their respective-,tangent tracks 74 up 75, as shown in. Fig. 7,v Where the steps move on an ascending incline from right to left and illustrate the arrangement of parts at the top of the getting-oli' landing'. The tracks 74 and 75 develop into channel tracks which extend from thence around the u per loop or carriage 8 as shown at 74, 76,7 in Fig.` 17. At the lower end of the loop 8 the channel tracks 77 merge again with the straight horizontal tracks 74 and 75 tangent to the upper gettinp'mn landing 11.

If the parts of Fig. 7 be now assumed to move on a deseending incline from left to right, the arrax-igement of the tracks at the lower end of /the upper loop 8 and at. the upper gettiugon landingr l] will be clear from an inspection of.' this ligure and Fig. 17. lVhen the. steps pass beyond-.the lower getting-oli' landing 14 the axle-whees ass .to and are carried upon tangent or s ralght horizontal tracks 74 and 75. If the parte of Fig. 7 be now assumed to niove from right to left on a descending incline, the tracks 74 and75 will illustrate the tangent tracks at the lower' gettingoif landing. Those tangent tracks develop into channel tracks 87 around the lower loop or carriage, as shown in` Fig. 19, and at the upper Iportion of this looifthe tracks 87 again merge into straight horizontal tracks 74 and 'V75 leading,r to and tangent to the getting-on landing l.

In the orniof step here shown each tread is provided with a single r1scr,'\vhich`- is adapted to perform its function on both -they ascending and descending runs.. For this purpose it is necessary to reverse the step so that the riser shall. be in serviceV on either run.

Referring now to Fig. 17 which is a diagrammatic View of the step movements ini the upper carriage 8, the Stationarj7 structure of the upper loop or carriage is provided with oppositely disposed guides for the` tros-k wher-ls 25 and 26, which preferably are in the form of channel guides or Ways 7S and 7i), respectively, and which are so located in the paths of travel ofthe truckivheels that the latter will pass into these guides when the axle wheels pass into the .channel extensions of the tracks 74 and 75.,

vIt is of course understood thai the channel trafks and guides ure provided for each end of the steps, although for clearness of illustration, I show the track und guides on 'hut one sido of the'structure, as for axle-V wheel 30 and theftruclewheels on the same side of the structure. the relation of the track and ,guides on the line Aw-Xof Fig. 17 lining shown in cross-section in Fig. 18. The' ,nides'78 and 79 follow the course of thetracks 74, and when the latter develop into the vertical run 76 the guides 7SV and 79 project oli-'either side in such relation as to 125: When the stepswmaintain the horizontal position of the tread, as shown in Fig. 1,7'. reach the lower port-ion of the vertical runs of thelrack 76 and guides 78' and 79, the

leading shaft .2.1 is momentarily stopped by descent of the truck-wheels 25 of the now` l the shoulders 80, formed b detlecting the i guides`78 inwardly toward tite tracks 79, thc truck-wheels 26 of the now rear shaft 28 c a in Fig. 17. The guide 79 connects with havin been shifted by the outwardly directe section 81 of the guide 7 9, so that the parts occupy the relative positions shown at an inwardl r directed guide section 82 and the guide 8 with an inwardly directed guide section 83, these sections crossing to opposite sides of the tracks 76. The walls of the channel uides 79 are suitably recessed or cut-away w ere these sections cross to allow the passage of the relatively wide truck-wheels 25. The guide section 83 is at an acute angle to the guide 78, and the guide section 82 is at an obtuse angle to the guide 79, and as the axle 29 moves along in its tracks 76, which at or about where the sections 82 and 83 cross begin to curve toward the horizont-al tracks =74 and which are tangent to ,the upper etting-ontlanding 11, the wheels 25 are t ragged-over the angular set-,tion 83 while the wheels 26 pass down through the reverse or crossing section 82, when -the )arts assume the positions indicated at b. vn this position the wheels 25V andv 26 have Crossed to opposite sides of the track 76, the structure being provided with suitable gaps where the channels 82 and 83 cross the chan nel 7G to accommodate the axles of the steps,

as shown in Fig. 17. The 'wheels 2G now travel along lower curved guidesections 84 which extend forwardly 'and approach the plane of the channel tracks 74 and 7 5, The wheels 25 travel through an upwardl Y-directed section 85 which effects a drag on the wheels so that the part-s assume the positions shown at c, and thence the wheels 25 travel in downwardly Ydirected sections 86 which serve to de ress the wheels 25 toward and ip rear of t ie wheels 30 and 31, as indicated at position d. When the wheels 25 and 20 reach t-he endif of the sections 84 and 8G the `tread surface of the step assumes the position at e, with its horizontal portieri upperf 'ably located aqli most and its riser in the lead. Also, the positions of the wheel-shafts are reversed,` as the shaft 27, which on the ascending run was the leading shaft now beizdnies the i'ollower, and the shaft 28 becomes the leading shaft on tlie descending run. The steps enter and leave the loop 1n horizontal position, and it is understood that shitablc4 guides ma belprovided for th-e truck-wheels `between t e ends of the tracks 70, 7 1, 72,

73, at thev upper getting-ott landing and the guides 78, 79, and also between the ends oi' the guides 84, 85, and the tracks 70,- 71, 72, 73, at the upper getting-on landing prefert le below normal level, in order that the Steps may Lg, ste-adied. It. is obvious, however, that this is provided by extending the tracks to' 'the guides.

From eeonsideration of the foregoing it will be apparent that as the steps pass over the tangent straight or level runs, the truck wheels 25 and 26 enter the channel guides 78 and 79, respectively, and the axle rollers 70 30 and 31 enter the channel tracks 74; as the steps proceed around the loop they are vcarried and supported by the axle rollers 30 and 3l. while the truck wheels and their cooperating channel guides serve primarily at 'I5 th ese. polnts as shunts or guides to control the step-unit 'and' reverse and changethe direction of the leadin edges of the steps. As the steps proceed own the vertical run the treads are maintained in substantiall hori` 80 4zontal position until the truck-whee s have moved throu h. the remaining sections to t-he point e, t e treads are in reversed position, being turned practically end to end so that. the' risers are onI the leading ed es and 85 the truck-wheels 26 have become the ending `wheels and the truck-wheels 25 have become the rear wheels of each respective step.V In this position the steps pass over the straight 4horizontal run leadingV tothe getting-on 90 landino 11 and tothe descent upon the inclme ii'om the upper level Vor story, and

Y when the steps pass upon the curved horizontal run the truclewlleels are brought-into cooperative relation with. their respective tracks 70, 71, 72, 73, to sustain and support" the steps, the axle-wheels a'gain becoming ln#y operative. When the steps go upon the descending incline, they are supported by the.'

tracks G8, 67, 68, 69, in step-form andin this relativo position and arran ement are car-` ried throughout the deseen mg incline.

When the steps reach the straight horizontal run of the lower` level the axle wheels 30 and 31 coperate with lower-105 channel tracks 87 arranged upon opposite sides of tl'ie frame and extending around the lower loop in the manner shown in Fig. 19, the axle wheels serving,lr to support and carry the steps during the course of their travel around this loop. The truck wheels pass into channel guides 88 and 89 which receive the wheels 2G and 25 respectively. The arrangement of parts is illustrated in Fig. 2l,

which is a section through one side of the lower carriage on the line C-C of Fig. 19, it of course being understood that similar provision is made for the other end of the steps on the oppsite'side of the structure. The lower channel upper channel guide 89 with-a downwardly extendingV section 91, the arrangement and disposition oi these sections being such that thev cross each other and lead to opposite 1 time the wheels 25 are carried `downwardly 130 guide 88 connects with 120 `an upwardly extendingsection 90 and the ceases in the sections 9L, as shown at o in Fig. 19, so that'the wheels 2G are above and the wheels :Z5 below tho track 87. and they then pass into parallel ysections 92 and 93 which maintain thil steps in approximate Vertical position with the wheels 26 above and in thc lead ot' the wheels 25 as shown at fu'. llarh of the upper parallel sections 92 is provided. with a Jog or stop 9-l'by which the wheels 26 are momentarily arrested so as to cause the steps to turn upon their axles 29 as centers and to throw the lower wheels 25 forward and in the lead of'the wheels 26, as shown at .1, the sections 93 extending in a curve 95 slightly toward the 'tracks Si'. In this position of the parts the steps are again reversed edge for edge and also turned over or lowerniost in then-nit. The channel track guides 95 are curved to I gradually approach the channel tracks 87. while the guides `for the wheels 26 beyond the stops 94 take a sudden dip as at 96 toward the channel tracks 87, this dip serving to form a drag for the wheels 2G, while the wheels 25 being free to move forward and to be turned upon the axle 29 as a center by reason of the detention of the wheels 26 travel around in their curved guides 95 and assume the lead, whereby the steps are restored to their original positions with the raisers upon the rear edges and with the upper faces of'the treads comingr into alinement as shown at y. As the steps pass forward around the end of the loop the front wheels 25 pass upon their guides 9.3 and the rear wheels 26 pass along,r guides 97 curved to conform to the curvature of the' tracks 87; the raides 97 terminutix in the horizontal trac rs 98, and the guides 95 are provided at their ends with downwardly directed portions 99 which de {lect the wheels 25 to the horizontal ends 100, so as to bring; the treads horizontal or uppermost. in the unit.

lt is of course understood that the guides SS and 89 may connect with the tracks 70, 7 l, 72, 73, of4 the curved horizontal getting ott' landing 14, and that the guides 99 and 100 may connect with similar tracks of the getting-on landing 2 in order to steady the steps. Wherethe steps emerge from below the floors at the getting-on iandin rs the supporting tracks ,of the truck-whee s are suitably elevated, and where they ass below the floors at the getting-olf lan ings theseV tracks are suitably. depressed.

In fthe -design of elevator here shown,

4. when the steps are carried around the terminal loops or carriages, the toothed edges of the links 44 and 51 are turned over so that the teeth face upwardly upon the return run or descending spiral or tread and engage withtthe ander sides of the driving sprockets, as shown in the lower half of Fig. 16. As the steps are uppermost in the carriage itis necessary to remove theshafts of -means the the driving sprockets from their path in thev`y` l return run. For this purpose the driving i' as shown at the lower portion of Fi I6.,

and are also provided with gear-whe@ s 101 and 102. respectively. with which a secondl pair of gears 103 and 104 mesh. The gea'rsl i 103 and lUllai-e keyed upon a`comniofn-shaft= 105 which is journal-ed in the' .framework below. the stub-axles a sufficient distance to allow for the clearance of the steps.

shaft for .transmitting power to; the outer driving'sprocketof any' p'aiiis. placed out of the way of the ste '-'By this4 return run where the teeth -of .thejlinks face upwardly aiid engage the'driving s rockets as shown in Fig. 16. .'It is also n'n erstood that the idler wheels 'G-'l and 65 on the retiirn run may be similarly iuountedpn stubaxles and provided with similar auxiliary shafts and gears.

As the inner linka e automatically adfjii ts.

its length to meetl t e requirements o .t e' positions ofthe steps on the inclines` and on the landings, the risers of the step be of such contour and configuration as 'to maintain Contact with the adjacent. treads in both positions of the'links.' For this'pnrpose provide a. waiied riser., which .as it approaches the ai'is o the machine becomes more nearly straight in. elevation. In lotting the curve of the riser, an arc of a circle is struck at the outer end of the tread with a radius e ual to the greatest' width of4 the segmento tread' and this aro is continued to correspon-d with the height of the-riser, as shown in Fi 23. .This are is intersected into any num er of equal divisions, and

is drawn to thil axis of tti, 'i iralor ceiill* of curvature. At an)7 Suitiib e points along.

the length of the tread and at a pointoorresponding to its inner or narrow eiid'ltlm radial lilies are intcrsect'ed by dividing lines spaced to 4correspond with, the spacingof the divisions or the outer arc, andthe intersections of` the radial and dividing lines mark the paths of arcs'which indicate the 15' curvature of' the riser at the points where these arcs are' located. It is obvious that.l the radial lines are parallel in elevation as shown in Fi 23 and tend to approach the same vertice iixis, and that the inner'end of the riser therefore tends to ,become straight in elevation as it approaches the' center of the machine. The arcs ofythe in'- 'i ner and outer ends of a riser that"`is 'attached to a. tread respectively 14 and 21 inches Wide at the ends is shown in F ig. 24.'

It is a parent that the loopsl or carriages impart fiterent rotations tothe steps to permit the axles of adjacent steps to pass or clear.

It is obvious that the double aniral fdim from each of suchintersections a radial lineulof 

